Invertible portable hand power-saw guides



Dec. 6, 1955 A, E, BROSTER ET AL 2,725,904

INVERTIBLE PORTABLE HAND POWER-SAW GUIDES Filed Aue 24. 1953 2 sheets-sheet 1 /6 fafa lli 7S /2 Dec. 6, 1955 A. E. BRosTER ET AL 2,725,904

INVERTIBLE PORTABLE HAND POWER-SAW GUIDES Filed Aug. 24. 1953 2 Sheets-Sheet 2 United States Patent O lNvEnmLE PORTABLE HAND POWER-SAW f GUIDES Alfred E. Broster and Walter H. Leslie, Island Falls, Saskatchewan, Canada This invention relates to invertible portable hand power-saw guides and the objects of the invention are:

l. To provide an inexpensive device of this class that can be carried by the carpenter from job to job and readily mounted on any suitable table made from material on the site of operations, and whereby selected angular seat and plumb cuts can be accurately made, particularly on rafters.

2. To guide a type of hand power-saw that may be tilted sideways and moved along a rectilinear path to produce an accurate angular cut, and a cut in which the angle is with respect to the top and bottom surfaces of the rafters.

3. To provide a tray which can be inverted on its table so that the saw carried vthereby may be inverted and used as a table saw, as hereinafter more particularly explained.

Broadly considered the invention consists of a tray longitudinally provided with parallel side anges between which the power-saw is guided along the bottom of the tray with the saw blade operating through a longitudinal slot formed in said bottom; a removable apertnred support on which said tray is pivoted, provided with graduations suitable for angular seat and plumb cuts on rafters, the said support being provided with a slot concentric with a pivotal point of said tray so that the tray may be moved into the desired angular position with relation to said pivotal point, and means to hold said tray in said position, as hereinafter more particularly explained.

Figure l is a plan view of the guide tray and its support, carrying a power-saw, mounted on a suitable table.

Figure 2 is chiefly a side elevation of Figure 1.

Figure 3 is perspective view of the inverted tray showing the saw in inverted position and mounted for use as a table saw.

Figure 4 is vertical cross section on the line 4 4, Figure 3.

Figure 5 (sheet 1) is an end view of the left-hand end of Figure 3 showing the fastening means for the inverted tray.

Figure 6 (sheet 2) is a plan view, on a reduced scale, of the slot-provided plate and the plates provided with graduations.

Fig. 7 is a plan View of the hinged end of the tray.

In the drawings like characters of reference refer to the same parts.

The tray 2, Figure l, is provided with parallel side flanges 3 which act as rectilinear guides for the base 4 of the power-saw generally indicated at 5. Formed in the iloor of the tray is a longitudinal slot 6 through which the saw blade 7 operates. Stops 8 are secured at both ends of the tray to limit the longitudinal movements of the power-saw.

The support for the tray consists of U-shaped plates 9 and 9 and a horizontal plate 10 to which latter the tray 2 is swivelled by the pin 10'. The top of the plate 10 and the top of plates 9 and 9 are in the same plane. The U-shaped supporting plates 9 and 9 are tted over Patented Dec. 6, 1955 carpenter on the job and is supported by a suitableV saw-horse 14 (Figure 3).

Formed in the top of the plate 10 is a slot 15 concentric to the swivel pin 10', and held in this slot is a headed bolt 16 holding a washer 17 against the underside of the plate 10. The bolt 16 extends through a longitudinal open short slot 18 formed at one end in the bottom of the tray 2 and through a slot 18' formed in one of the stops 8. By means of a washer-provided wing-nut 19 on the bolt 16, the tray is held securely in set position for making angular cuts.

Although the plate 10 and the U-shaped plates 9 and 9 are shown as separately formed in Figures 1 and 2 they may be cast in one piece.

Any conventional type of hand power-saw may be used with this device and these saws are usually constructed to be vertically and angularly adjustable in position for use.

The slot 6 is of convenient width and location with respect to the flanges 3 to permit of any tilting of the saw blade.

Referring to Figure l it will be noticed that the top of the plate 9 is provided with graduations collectively indicated by the numeral 20. These markings indicate respectively angles of a pitch of 1/2 Vwith a 12 inch rise; a

1/3 pitch with an 8 inch rise, and a 1A pitch with a 6 inchrise. The markings on the top of the plate 9 are collectively indicated at 21 and are indicated respectively as a 1A pitch with a 6 inch rise; a 1/3 pitch with an 8 inch rise, and a 1/2 pitch with a 12 inch rise. Other graduations may of course be marked on these plates.

To cut rafters at the desired angle the' outer side of the appropriate flange 3 of the tray 2, as this latter is swung on its swivel 10', is placed in alignment with the score mark of a given graduation and then the tray is clamped firmly in place by the wing nut 19 on the bolt 16.

Since the rafters must be cut through, the opposing inner ends of the plates 9 and 9', and the plate 10 adjacent thereto, are formed as shown at A, in Figure 6 to provide clearance therewith of the saw-blade while it works.

Figure 3 shows the tray and power-saw in an inverted position for use as a table-saw.

To permit the inversion of the tray 2 the saw is moved into position between the side members 11 and 11 and the U-shaped holding-pin 22 (Figure 4) is passed through the holes 23 formed in alignment in both of the anges 3, over the base plate 4 of the saw, vthus clamping the Carried by the vertical wall 24 of the plate 10, is a hinge 25 (Figure 5 and through one of the wings thereof is passed a headed bolt 26. (Figures 2 and 5.) This bolt 26 is raised into vertical position on its hinge 2S and then the inverted ytray 2 is slid along the plate 10. until the slot 18 straddles the bolt 26 and the head 30 of this bolt is housed in the recess 29 formed in the slotted stop 8. By screwing the wing-nut 28 against the horizontal wing of the hinge the bolt 26 and the tray and saw are securely held in place. 

